How to make a rope curving in a certain way
It's easy to lose bits if their origins aren't in the right place. Here's one approach to your job: I hope the loops are circular enough for you. Working in the XY plane..

The curve:

(As suggested by @Robert Roth)


Make an unfilled 6-sided mesh circle, ShiftD duplicate it in Edit Mode, X delete a couple of edges, and F join the loose ends.
Then, in Object Mode, AltC convert the mesh to a curve. With all vertices selected,  In the Tool region, set the Spline Type to Bezier, and V convert all the vertices to 'Auto'


There may be a bit of tweaking to do...



Note where the origin of the curve is: at world 0. When you create the profile / set up your rope, to make things easier, put its origin at the same place. Make sure all object-level transforms of the rope (especially scale) are applied.

The rope:
(For example)


A little trefoil profile, made out of 3 6-sided unfilled circles, snapped together, doubles removed, internal edges removed.
With all vertices selected, ShiftAltOSet Origin to geometry, and set the transform of the profile object to (0,0,0) Now everything is lined up.
Screw modifier, 120 degrees
Array modifier, relative Z, Merge on, Count to fit the curve.
Curve modifier, Deformation Axis Z, target: the curve
Subdivision modifier, level 1




With this sort of result:



EDIT: (response to @Teglik)

You can manipulate the path-mesh in various ways: here, working on the left half, E extending terminal vertices, and R rotating and  S scaling the new vertices in/out from the 3D cursor at the origin, before duplicating and rotating the whole left half through 180 to make the right half, F joining the ends, before converting to a curve.